package hy.集合;

import java.util.*;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.CopyOnWriteArrayList;

public class Test1 {
    public static void main(String[] args) {
        CopyOnWriteArrayList c = new CopyOnWriteArrayList();
        c.add("abc");
        c.get(0);
        Hashtable t = new Hashtable();
        t.put("","");
//        t.get()
        Properties p;
        TreeMap tr = new TreeMap();
        tr.put("","");
        //1000-->1024
        HashMap hm = new HashMap(1000);
        hm.put("","");
        ConcurrentHashMap cc = new ConcurrentHashMap();
        cc.put("","");
        ArrayList arr = new ArrayList();
        arr.add("");


    }
}
